Trim rings for automobile wheels are very well known in the art. These rings generally comprise a shaped sheet metal collar to which is affixed an outer retaining ring. The outer ring is a stamped sheet member usually of stainless steel, suitably secured to the trim ring, the member having a plurality of spaced retention teeth designed to grip the wheel to which attached. The trim ring itself provides an exterior cover for the wheel rim which overlies the retention ring and wheel rim.
The retention ring is generally a rigid hoop shaped member which is clinched at one edge to one edge of the trim ring. The retention ring by its construction has its own structural rigidity to provide retention teeth disposed therefrom. The retention ring maintains the nominal diameter of the retention teeth and since the teeth are integral thereto the inherent construction provides the holding force for the retention teeth.
The usual trim ring and method of fabricating same combines two separate and individual components, i.e. (a) the retention ring with various types of retention tooth forms, and (b) the decorative or outer visible trim portion, with each part having individual processing procedures and tools. In the two piece structure, much material is wasted in die blanking and drawing the trim ring section, as the center portion is blanked out and considered scrap, and can only be used in the manufacture of some part using this type and size of material, otherwise it is considered and sold as scrap.